How Can We Reliably Detect Semi-Colon Terminated C For and While Loops?

Detecting Semi-Colon Terminated C for & While Loops via Regular Expression

In Python, matching C for and while loops terminated with a semi-colon using a regular expression can be challenging due to the possibility of nested parentheses within the loop statement.

One approach to this problem without using a regular expression is to employ a simple algorithm:

1. Initialize a position counter pos to point to the character just before the opening parenthesis of the loop.
2. Set an open bracket counter openBr to 0.
3. Increment pos and read each character.
4. If the character is an opening bracket, increment openBr.
5. If the character is a closing bracket, decrement openBr.
6. Repeat steps 3-5 until openBr returns to 0.
7. Stop at the current pos, which now points to the closing bracket of the loop.

At this point, verify the presence of a semi-colon after the closing bracket to determine if the loop termination is valid.

This algorithm provides a straightforward and reliable method for detecting semi-colon terminated C for and while loops, eliminating the complexities associated with regular expressions.

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